![Page 1: Relational Model: Examples. Banking Example branch (branch_name, branch_city, assets) customer (customer_name, customer_street, customer_city) account](https://reader035.vdocuments.mx/reader035/viewer/2022062518/56649e415503460f94b33c53/html5/thumbnails/1.jpg)
Relational Model:Relational Model:ExamplesExamples
![Page 2: Relational Model: Examples. Banking Example branch (branch_name, branch_city, assets) customer (customer_name, customer_street, customer_city) account](https://reader035.vdocuments.mx/reader035/viewer/2022062518/56649e415503460f94b33c53/html5/thumbnails/2.jpg)
Banking ExampleBanking Example
branch (branch_name, branch_city, assets)
customer (customer_name, customer_street, customer_city)
account (account_number, branch_name, balance)
loan (loan_number, branch_name, amount)
depositor (customer_name, account_number)
borrower (customer_name, loan_number)
![Page 3: Relational Model: Examples. Banking Example branch (branch_name, branch_city, assets) customer (customer_name, customer_street, customer_city) account](https://reader035.vdocuments.mx/reader035/viewer/2022062518/56649e415503460f94b33c53/html5/thumbnails/3.jpg)
Banking ExampleBanking Example
branch (branch_name, branch_city, assets)
customer (customer_name, customer_street, customer_city)
account (account_number, branch_name, balance)
loan (loan_number, branch_name, amount)
depositor (customer_name, account_number)
borrower (customer_name, loan_number)
![Page 4: Relational Model: Examples. Banking Example branch (branch_name, branch_city, assets) customer (customer_name, customer_street, customer_city) account](https://reader035.vdocuments.mx/reader035/viewer/2022062518/56649e415503460f94b33c53/html5/thumbnails/4.jpg)
Example Example branch branch relationrelation
![Page 5: Relational Model: Examples. Banking Example branch (branch_name, branch_city, assets) customer (customer_name, customer_street, customer_city) account](https://reader035.vdocuments.mx/reader035/viewer/2022062518/56649e415503460f94b33c53/html5/thumbnails/5.jpg)
Example Example loanloan relation relation
![Page 6: Relational Model: Examples. Banking Example branch (branch_name, branch_city, assets) customer (customer_name, customer_street, customer_city) account](https://reader035.vdocuments.mx/reader035/viewer/2022062518/56649e415503460f94b33c53/html5/thumbnails/6.jpg)
Example Example borrowerborrower relation relation
![Page 7: Relational Model: Examples. Banking Example branch (branch_name, branch_city, assets) customer (customer_name, customer_street, customer_city) account](https://reader035.vdocuments.mx/reader035/viewer/2022062518/56649e415503460f94b33c53/html5/thumbnails/7.jpg)
Example QueriesExample Queries
Find all loans of over $1200
Find the loan number for each loan of an amount greater than $1200
amount > 1200 (loan)
loan_number (amount > 1200 (loan))
Find the names of all customers who have a loan, an account, or both, from the bank
customer_name (borrower) customer_name (depositor)
![Page 8: Relational Model: Examples. Banking Example branch (branch_name, branch_city, assets) customer (customer_name, customer_street, customer_city) account](https://reader035.vdocuments.mx/reader035/viewer/2022062518/56649e415503460f94b33c53/html5/thumbnails/8.jpg)
Example QueriesExample Queries
Find the names of all customers who have a loan at the Perryridge branch.
Find the names of all customers who have a loan at the Perryridge branch but do not have an account at any branch of the bank.
customer_name (branch_name = “Perryridge”
(borrower.loan_number = loan.loan_number(borrower x loan))) –
customer_name(depositor)
customer_name (branch_name=“Perryridge”
(borrower.loan_number = loan.loan_number(borrower x loan)))
![Page 9: Relational Model: Examples. Banking Example branch (branch_name, branch_city, assets) customer (customer_name, customer_street, customer_city) account](https://reader035.vdocuments.mx/reader035/viewer/2022062518/56649e415503460f94b33c53/html5/thumbnails/9.jpg)
Example QueriesExample Queries
Find the names of all customers who have a loan at the Perryridge branch.
Query 2
customer_name(loan.loan_number = borrower.loan_number (
(branch_name = “Perryridge” (loan)) x borrower))
Query 1
customer_name (branch_name = “Perryridge” (
borrower.loan_number = loan.loan_number (borrower x loan)))
![Page 10: Relational Model: Examples. Banking Example branch (branch_name, branch_city, assets) customer (customer_name, customer_street, customer_city) account](https://reader035.vdocuments.mx/reader035/viewer/2022062518/56649e415503460f94b33c53/html5/thumbnails/10.jpg)
Example QueriesExample Queries
Find the largest account balance
Strategy:
Find those balances that are not the largest
– Rename account relation as d so that we can compare each account balance with all others
Use set difference to find those account balances that were not found in the earlier step.
The query is:
balance(account) - account.balance
(account.balance < d.balance (account x d (account)))
![Page 11: Relational Model: Examples. Banking Example branch (branch_name, branch_city, assets) customer (customer_name, customer_street, customer_city) account](https://reader035.vdocuments.mx/reader035/viewer/2022062518/56649e415503460f94b33c53/html5/thumbnails/11.jpg)
Bank Example QueriesBank Example Queries
Find the names of all customers who have a loan and an account at bank.
customer_name (borrower) customer_name (depositor)
Find the name of all customers who have a loan at the bank and the
loan amount
customer_name, loan_number, amount (borrower loan)
![Page 12: Relational Model: Examples. Banking Example branch (branch_name, branch_city, assets) customer (customer_name, customer_street, customer_city) account](https://reader035.vdocuments.mx/reader035/viewer/2022062518/56649e415503460f94b33c53/html5/thumbnails/12.jpg)
Query 1
customer_name (branch_name = “Downtown” (depositor account ))
customer_name (branch_name = “Uptown” (depositor account))
Bank Example QueriesBank Example Queries
Find all customers who have an account from at least the “Downtown” and the Uptown” branches.